usb: dwc3: Allocate fixed h/w eps for GSI endpoints

Adds support to allocate specific hardware EPs to
GSI enabled endpoints. Creates EP list with names
"gsi-epin" for IN and "gsi-epout" for OUT EPs that
are intended for use by the GSI function driver.
The EPs are reserved from the end of the EP list.

CRs-Fixed: 1003784
Change-Id: I70ebce8c2717baaea38f7b6235976d8a522eb9fd
Signed-off-by: Devdutt Patnaik <dpatnaik@codeaurora.org>

2 files changed, 38 insertions, 11 deletions

diff --git a/drivers/usb/dwc3/dwc3-msm.c b/drivers/usb/dwc3/dwc3-msm.c
index cb174654ff27..3ad858487b81 100644
--- a/drivers/usb/dwc3/dwc3-msm.c
+++ b/drivers/usb/dwc3/dwc3-msm.c
@@ -1053,11 +1053,6 @@ static void gsi_free_trbs(struct usb_ep *ep)
 		dep->trb_pool = NULL;
 		dep->trb_pool_dma = 0;
 		dep->trb_dma_pool = NULL;
-		/*
-		 * Reset the ep_type to NORMAL, for next compostion
-		 * switch which may be non-gsi.
-		 */
-		dep->endpoint.ep_type = EP_TYPE_NORMAL;
 	}
 }
 /*
@@ -1078,9 +1073,6 @@ static void gsi_configure_ep(struct usb_ep *ep, struct usb_gsi_request *request)
 
 	memset(&params, 0x00, sizeof(params));
 
-	/* Set the ep_type as GSI */
-	dep->endpoint.ep_type = EP_TYPE_GSI;
-
 	/* Configure GSI EP */
 	params.param0 = DWC3_DEPCFG_EP_TYPE(usb_endpoint_type(desc))
 		| DWC3_DEPCFG_MAX_PACKET_SIZE(usb_endpoint_maxp(desc));
diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
index f146b965b2c4..dc10f299b2a6 100644
--- a/drivers/usb/dwc3/gadget.c
+++ b/drivers/usb/dwc3/gadget.c
@@ -754,6 +754,13 @@ static int dwc3_gadget_ep_disable(struct usb_ep *ep)
 		return 0;
 	}
 
+	/* Keep GSI ep names with "-gsi" suffix */
+	if (!strnstr(dep->name, "gsi", 10)) {
+		snprintf(dep->name, sizeof(dep->name), "ep%d%s",
+			dep->number >> 1,
+			(dep->number & 1) ? "in" : "out");
+	}
+
 	spin_lock_irqsave(&dwc->lock, flags);
 	ret = __dwc3_gadget_ep_disable(dep);
 	dbg_event(dep->number, "DISABLE", ret);
@@ -2142,11 +2149,27 @@ static const struct usb_gadget_ops dwc3_gadget_ops = {
 
 /* -------------------------------------------------------------------------- */
 
+#define NUM_GSI_OUT_EPS	1
+#define NUM_GSI_IN_EPS	2
+
 static int dwc3_gadget_init_hw_endpoints(struct dwc3 *dwc,
 		u8 num, u32 direction)
 {
 	struct dwc3_ep			*dep;
-	u8				i;
+	u8				i, gsi_ep_count, gsi_ep_index = 0;
+
+	/* Read number of event buffers to check if we need
+	 * to update gsi_ep_count. For non GSI targets this
+	 * will be 0 and we will skip reservation of GSI eps.
+	 * There is one event buffer for each GSI EP.
+	 */
+	gsi_ep_count = dwc->num_gsi_event_buffers;
+	/* OUT GSI EPs based on direction field */
+	if (gsi_ep_count && !direction)
+		gsi_ep_count = NUM_GSI_OUT_EPS;
+	/* IN GSI EPs */
+	else if (gsi_ep_count && direction)
+		gsi_ep_count = NUM_GSI_IN_EPS;
 
 	for (i = 0; i < num; i++) {
 		u8 epnum = (i << 1) | (!!direction);
@@ -2160,9 +2183,21 @@ static int dwc3_gadget_init_hw_endpoints(struct dwc3 *dwc,
 		dep->direction = !!direction;
 		dwc->eps[epnum] = dep;
 
-		snprintf(dep->name, sizeof(dep->name), "ep%d%s", epnum >> 1,
-				(epnum & 1) ? "in" : "out");
+		/* Reserve EPs at the end for GSI based on gsi_ep_count */
+		if ((gsi_ep_index < gsi_ep_count) &&
+				(i > (num - 1 - gsi_ep_count))) {
+			gsi_ep_index++;
+			/* For GSI EPs, name eps as "gsi-epin" or "gsi-epout" */
+			snprintf(dep->name, sizeof(dep->name), "%s",
+				(epnum & 1) ? "gsi-epin" : "gsi-epout");
+			/* Set ep type as GSI */
+			dep->endpoint.ep_type = EP_TYPE_GSI;
+		} else {
+			snprintf(dep->name, sizeof(dep->name), "ep%d%s",
+				epnum >> 1, (epnum & 1) ? "in" : "out");
+		}
 
+		dep->endpoint.ep_num = epnum >> 1;
 		dep->endpoint.name = dep->name;
 
 		dwc3_trace(trace_dwc3_gadget, "initializing %s", dep->name);